| A lionesses in a game reserve in Kenya. (AFP)
Okavango Delta (Botswana), Oct. 25: Aids is not only killing millions of people in Africa. There is growing concern it is also killing lions and driving the king of the jungle to the brink of extinction.
With scientists reporting a devastating collapse of the African lion population from 230,000 in 1980 to fewer than 20,000 now, the decline has traditionally been blamed on loss of natural habitat and hunting. But advances in virology and ground-breaking field research suggest that large numbers of lions could be dying from Aids because their immune system has been destroyed by lion lentivirus, the lion version of HIV.
Much of the research into lion AIDS is being carried out in Botswana, the African country of just 1.7 million people which has the highest recorded rate of HIV infection in the world — 40 per cent in some towns.
To the layman, the Okavango Lion Conservation Project in Botswana suggests clear parallels between human and lion AIDS. After the British researcher Kate Nicholls and her Dutch partner, Pieter Kat, successfully tracked a male and female lion to a zebra kill, they watched as the lioness, Fixin, named after a wine — in this case a burgundy — like all the research animals, padded away a short distance and started to roar. “We know these animals very well and we know she has three cubs she is calling forward to feed,” Kat explained.
As the shadows of circling vultures flicked across the lioness’ back, she stared in the direction her young should have come from, but they did not appear. Later in the day the three cubs were found, thin and listless, with scrawny hind-quarters and matted, ropey coats. “These were healthy, bouncy cubs just a few weeks ago and even though there is plenty of food here and plenty of water they are already this sick,” Nicholls said.
“We know that all the adults in this group have the lentivirus and it is hard not to see the parallels between a human AIDS victim wasting away and what we are seeing here.”
The pair have been working for six years in the same region of the Okavango Delta, one of Africa’s last wilderness areas large enough to support a significant population of lions and other predators.
Using radio collars to track key members of four prides, and sometimes taking blood samples from adult lions, they have concluded that lion AIDS is much more significant than previously believed.
Much of the work is distinctly unglamorous. Nicholls is thrilled if she can gather a bag of delta sand recently urinated on by one of the research lions, as with the help of a centrifuge this provides a good urine sample. “Hormones can be checked in the urine and I believe hormones are key to understanding the healthy life cycle of the lion and explaining how it might go wrong,” she said.
It is problems with reproduction and fertility among their lions that first raised suspicion about lion AIDS.
During their research time, the couple identified 104 cubs born within the prides but fewer than 10 reached adulthood. “Such a high mortality rate coupled with cases of pregnant lionesses losing cubs before birth and others failing to become pregnant raised our suspicions,” Nicholls said.
“More work needs to be done on the effect of the lentivirus on lions and we are really lucky with the recent advances in technology for identifying and working on the virus.”
Samples from the research team have recently been sent to the Retrovirus Research Laboratory at the University of Glasgow where senior researcher Brian Willett is convinced more needs to be done to study lion AIDS. “The problem with African lions is that if they are sick from the virus they will not last five minutes out in the wild,” Willett said.
While no other animal could be infected by eating a diseased lion, he added: “If they are torn to pieces by the other predators it is pretty difficult to establish if sickness was caused by the virus.
But with the technology we now have and with enough testing of the animals we can get a fairly good idea how the virus works and how it effects other pathogens that might make the animal sick.”